PLANNED SINCE THE FIFTIES: As work wound down on the Baltimore Harbor Tunnel (I-895) in 1957, the Maryland State Roads Commission suggested that a second tunnel beneath Baltimore Harbor. Believing such a tunnel could be integrated into the Interstate highway network then under development, the state began location studies for the proposed tunnel. In 1958, the state purchased 17 acres of a 137-acre tract held by the General Services Administration at Hawkins Point, but did not pursue any further action.

With the original four-lane Harbor Tunnel exceeding full design capacity at roughly 65,000 vehicles per day (AADT) by 1964 and projections for 1980 at double this level, the State Roads Commission advocated construction of a second four-lane tunnel between Hawkins Point and Sollers Point ahead of a parallel Chesapeake Bay Bridge (US 50 and US 301). Commission Chairman John Funk called the second harbor crossing "a bread-and-butter, 52-weeks a year proposition," while calling the second bay bridge "a four months a year problem." The state estimated the cost of the proposed Outer Baltimore Harbor Crossing, which comprised a four-lane tunnel and approach highways that were to complete the Baltimore Beltway (I-695), at between $150 million and $175 million (in 1964 dollars).

TUNNEL PLANS GET STOPPED IN THE WATER: In 1968, the State Roads Commission sold $220 million in bonds to cover the projected costs of the four-lane tunnel and its approach highways, as well as additional funds to pay for the parallel Chesapeake Bay Bridge. This was seen as a first step toward reality for the Outer Baltimore Harbor Crossing. However, with construction costs rising rapidly, the state scaled back of the scope of the project from a twin-tube, four-lane tunnel to a single-tube, two-lane tunnel.

Initial test borings were made for the tunnel beneath Baltimore Harbor in 1969, and work on the causeway and viaduct approaches began early in 1970. In July of that year, the State Roads Commission entertained bids for the tunnel. Even given the reduced scope of the project, the relatively high bids on the tunnel project alone - which ranged from $50 million to $60 million - prompted the state to pursue a four-lane bridge alternative. The state received a $19.5 million bid for the bridge's substructure in August 1972, followed by a $30.7 million bid for the superstructure two months later.

DESIGN AND CONSTRUCTION: The Maryland Transportation Authority (MdTA), which took over jurisdiction of the state's toll roads and water crossings in 1971, commissioned J.E. Greiner, a leading Baltimore-based engineering design firm (and now part of the URS Corporation), to oversee construction of the bridge. A conventional suspension design was considered for the crossing, but the idea was abandoned over concerns about the cost and size of the anchorages.

Engineers finally decided upon a continuous steel truss design that had a 1,200-foot-long main span (between piers) - which at the time was to be longest continuous-truss span in the United States - and two 722-foot-long side spans. Borrowing from the design of many steel arch spans, the main truss span is suspended by steel cables. On both sides of the three-span truss bridge were three 300-foot-long girder spans to the west and six girder spans of identical length to the east; these spans were hoisted onto the bridge in their entirety to reduce construction costs. A series of shorter spans built on fill (causeway) connected the bridge to the mainland. The bridge was built to accommodate four 12-foot-wide vehicular lanes, but there are no shoulders. A four-foot-wide concrete ("Jersey") barrier separates opposing traffic flows.

Construction was plagued by faulty concrete work on the main piers of the bridge, as well as by the death of a construction worker when a shaft of steel rods collapsed. The bridge was opened to traffic on March 23, 1977 at a cost of $60 million, about 15 months behind schedule and $10 million over budget. Including the nearly 11 miles of approaches, the cost of the Outer Crossing project was $136 million. Completion of the span brought the 26-year-old Baltimore Beltway project to its conclusion.

Shortly before the bridge opened, it was renamed in honor of Francis Scott Key, who penned the "Star-Spangled Banner" at nearby Fort McHenry during the War of 1812.

BRINGING THE APPROACHES UP TO INTERSTATE STANDARDS: When they were built between 1970 and 1973, the approaches leading to the Francis Scott Key Bridge were designed under the assumption that there was to be a two-lane tunnel, not a four-lane bridge. This included the 3,379-foot-long drawbridge over Curtis Creek near Hawkins Point (west of the Key Bridge) and the 3,907-foot-long viaduct over Bear Creek near Sparrows Point (east of the Key Bridge). Because these approaches were not up to Interstate standards, along with the fact that the Outer Baltimore Harbor Crossing was not one of the original Interstate routes planned for Baltimore, the completed project received the MD 695 designation.

The MdTA built a parallel drawbridge over Curtis Creek for the beltway extension between 1978 and 1981. The completion of this project brought four lanes of traffic capacity on the Baltimore Beltway extension from the Arundel Expressway (MD 10) to the Francis Scott Key Bridge. In the closed position, the Curtis Creek drawbridges provide 60 feet of vertical clearance. The beltway bridge over Curtis Creek parallels the adjacent four-lane MD 173 bridge over Curtis Creek, which also was built during the 1970's.

Work on upgrading the easterly Sollers Point-Sparrows Point approach took much longer. When this approach was built, the nearby Bethlehem Steel-Sparrows Point complex (now known as Baltimore Marine Industries, Inc.) was a very active shipbuilding and repair facility, requiring the construction of a two-lane, 3.5-mile-long viaduct to cross the 16 roads and two railroads that served the complex. However, the scaling down of operations at the Sparrows Point Bethlehem Steel prompted the MdTA to consider replacing the two-lane viaduct with a four-lane surface freeway. The $89.5 million project began in 1995, and by 1998 the two-lane eastbound roadway opened to two-way traffic. Work began soon thereafter on demolishing the old viaduct, which later became the right-of-way for the two-lane westbound roadway. The project, which included the twinning of the span over Bear Creek, as well as simplified interchanges at MD 157 (Peninsula Expressway) and MD 151 (North Point Boulevard), was completed in January 2000.

Although the entire length of the Baltimore Beltway was not up to Interstate standards until the Sollers Point-Sparrow Point upgrade was completed, I-695 shields began to appear along the MD 695 segment of the beltway as early as 1988.

In 2004, the MdTA converted the far left toll lanes northbound and southbound into 30 MPH "high speed" EZ-Pass lanes at the existing toll plaza. Given the success of these lanes, the agency plans to spend $22 million through 2010 to install new express lanes at the Fort McHenry and Harbor tunnels, as well as on the John F. Kennedy Memorial Highway (I-95).

PROTECTING THE KEY BRIDGE: According to the MdTA, the Francis Scott Key Bridge carries approximately 31,000 vehicles per day. The bridge serves as popular route for through trucks unable to use the Fort McHenry and Harbor tunnels.

However, the prospect of overweight and unsafe cargo prompted the MdTA to address security risks, especially in wake of a 2005 terror threat that closed both tunnels for hours. Work began in July 2006 on a $26.5 million project to provide a security inspection and weigh station along the eastbound lanes of I-695 at EXIT 1 (Quarantine Road), just before the Hawkins Point approach to the Key Bridge. The project, which moved the eastbound EXIT 1 exit and entrance ramps east to Fort Armistead Road, was completed in September 2008.

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